Advanced laser protection devices based on thermally fixed hidden gratings and reversed-mode PSCT light switches

This proposal is to develop a non focal plane laser protection device for the Army and other DoD agencies. The device will be composed of single-crystal plates with hidden reflective/diffraction gratings, which can be revealed with exposure to strong pulsed or continuous laser, and a reversed-mode polymer-stabilized-cholesteric-texture (PSCT) light switch. This proposed device can change from a high transmission state (80%) to a very low transmission state (35 50 dB) to block strong light pulse or continuous within short time scale (subnanosecond). In the entire visible and NIR waveband, higher transmittance is anticipated with efforts on deposition of anti-reflective coatings. This protection device features large in aperture, broad in transparent window and in field of view, wavelength-insensitive, and fast in response.